The electrical storage battery on a motorized vehicle has historically been a crucial component, the battery being used not only as a source of energy for cranking the vehicle's engine during a startup, but also as a ballast for storing electrical energy, in conjunction with the charging system and voltage regulation circuitry during vehicle operation. The battery has to have adequate state of charge for starting the vehicle's engine, in the variety of environmental conditions in which the vehicle is to be operated, including a wide range of temperature extremes.
In modern versions of motorized vehicles, the battery serves the additional function of supplying electrical currents to various systems other than the vehicle's starter motor during start-up. Such systems may include vehicle security systems, which periodically “wake up”, or are called to wake up by the vehicle's operator. Other such systems include keyless remote wireless access devices. In addition, electronic control systems (“ECS”) for engine and accessory management during operation rely on an electrical system featuring a battery. Thus, a battery is desirously of high reliability to ensure proper and complete vehicle design functionality. Hence, failure of the battery may manifest itself in several symptoms, including a vehicle no-start situation.
Battery “parasitic load” is the electrical load presented on a vehicle when the ignition key is in the off position, which load may be constant or intermittent. Excessive parasitic load can drain a battery to a low state of charge (“SOC”) which can prevent the vehicle from being started at a later point in time. Furthermore, a relatively low SOC can be harmful to battery life, especially for batteries which are not designed to tolerate repeated deep charge cyclings. This may be most pronounced in modern vehicles as the number of on-board computer modules which need to wake up periodically during ignition-off situation are increased.
Conditions of excessive parasitic load may be easy to detect, but if there is no means to readily address the issue then the battery SOC could become substantially depleted resulting in a no start condition. Accordingly, there is a desire to process for detecting and resolve battery drain due to excessive parasitic current.